A cylinder head of an internal combustion engine having an integrated exhaust manifold requires more flow-through of lubricating oil than engines having conventional cylinder heads. In such an arrangement, the integrated exhaust manifold requires the lubrication oil drainbacks to be packaged around the integrated exhaust port. Packaging the cross-sectional area required for proper engine function typically yields large drain areas for returning the circulated lubricating oil back to the engine oil pan areas.
While the larger drain areas provide effective lubricating oil flow patterns, they also increase the risk that improperly assembled and loose valvetrain components, such as a roller-finger follower or a valve retainer, may pass down to the cylinder block and oil pan areas. This situation can lead to catastrophic engine failure and/or reduced engine performance. Extensive service and disassembly time is required should valvetrain components need to be retrieved from oil pan areas.
As in so many areas of vehicle technology there is always room for improvement related to the use and operation of gaskets arrangements provided between cylinder blocks and cylinder heads in internal combustion engines.